Re: [PATCH] coresight: tpdm: initialize spinlock before exposing sysfs

From: yingchao deng

Date: Sun Sep 06 2026 - 23:13:08 EST


Gentle reminder

On 25/08/2026 10:06, yingchao wrote:
From: Yingchao Deng <dengyingchao@xxxxxxxxxxxxxxx>

tpdm_probe() initializes drvdata->spinlock after coresight_register(), but
the sysfs attributes registered by coresight_register() use the spinlock.
This exposes a window where a concurrent sysfs write can lock an
uninitialized spinlock.

Initialize the spinlock before coresight_register().

Fixes: b3c71626a933 ("Coresight: Add coresight TPDM source driver")
Signed-off-by: Yingchao Deng <dengyingchao@xxxxxxxxxxxxxxx>
---
drivers/hwtracing/coresight/coresight-tpdm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index 8464edbba2d4..50d1351772b9 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -1457,12 +1457,12 @@ static int tpdm_probe(struct device *dev, struct resource *res)
desc.groups = tpdm_attr_grps;
else
desc.groups = static_tpdm_attr_grps;
+ spin_lock_init(&drvdata->spinlock);
+
drvdata->csdev = coresight_register(&desc);
if (IS_ERR(drvdata->csdev))
return PTR_ERR(drvdata->csdev);
- spin_lock_init(&drvdata->spinlock);
-
return 0;
}